Hand-Held Tool Gear Mechanism Unit

ABSTRACT

A hand-held tool gear mechanism unit includes a drive gearwheel, an output gearwheel, and a connecting unit. The output gearwheel has a rotational axis spaced apart radially from a rotational axis of the drive gearwheel. The connecting unit is configured to transmit a rotational movement from the drive gearwheel to the output gearwheel substantially without a step-up transmission ratio. The connecting unit is configured to couple the drive gearwheel and the output gearwheel such that they can be moved relative to one another about a pivot axis.

This application is a divisional application of copending U.S.application Ser. No. No. 14/075,253, filed on Nov. 8, 2013, which claimspriority under 35 U.S.C. §119 to patent application no. DE 10 2012 220415.6, filed on Nov. 9, 2012 in Germany, the disclosures of which areeach incorporated herein by reference in their entirety.

BACKGROUND

A hand-held tool gear mechanism unit has already been proposed having adrive gearwheel, having an output gearwheel which has a rotational axiswhich is spaced apart radially from a rotational axis of the drivegearwheel, and having a connecting unit which transmits a rotationalmovement from the drive gearwheel to the output gearwheel substantiallywithout a step-up transmission ratio.

SUMMARY

The disclosure proceeds from a hand-held tool gear mechanism unit havinga drive gearwheel, having an output gearwheel which has a rotationalaxis which is spaced apart radially from a rotational axis of the drivegearwheel, and having a connecting unit which transmits a rotationalmovement from the drive gearwheel to the output gearwheel substantiallywithout a step-up transmission ratio.

It is proposed that the connecting unit is provided for coupling thedrive gearwheel and the output gearwheel such that they can be movedrelative to one another about a pivot axis. A “drive gearwheel” is to beunderstood to mean, in particular, a gearwheel which is arranged interms of action, in particular, directly in front of the connectingunit. The drive gearwheel is preferably arranged in terms of actionbetween a gear mechanism of a drive unit of a hand-held tool and theconnecting unit. In at least one operating state, the gear mechanism ofthe drive unit reduces a rotational speed of a motor of the drive unit.An “output gearwheel” is to be understood to mean, in particular, agearwheel which is arranged in terms of action, in particular, directlybehind the connecting unit. The output gearwheel is preferably arrangedin terms of action between the connecting unit and an insertable toolfastening means of the hand-held tool gear mechanism unit. The outputgearwheel is advantageously connected fixedly to the insertable toolfastening means so as to rotate with it. “Spaced apart radially” is tobe understood to mean, in particular, that the rotational axis of thedrive gearwheel and the rotational axis of the output gearwheel are at aspacing in a direction perpendicularly with respect to at least one ofthe rotational axes. The rotational axis of the drive gearwheel and therotational axis of the output gearwheel are preferably at a spacing ofgreater than 2 mm, advantageously greater than 4 mm, particularlyadvantageously greater than 8 mm, along a rotational axis of theconnecting unit. The rotational axis of the drive gearwheel and therotational axis of the output gearwheel are preferably at a spacing ofless than 40 mm, advantageously less than 30 mm, particularlyadvantageously less than 20 mm, along the rotational axis of theconnecting unit. The rotational axis of the drive gearwheel and therotational axis of the output gearwheel can preferably be oriented inparallel. A “connecting unit” is to be understood to mean, inparticular, a unit which connects the drive gearwheel and the outputgearwheel directly in terms of action. All the parts of the connectingunit are preferably connected fixedly to one another so as to rotatetogether. As an alternative, the connecting unit could have two or, inparticular, three gearwheels which are in engagement with one another.In this context, “transmit a rotational movement” is to be understood tomean, in particular, that, during operation, the drive gearwheel drivesthe connecting unit and the connecting unit drives the output gearwheel.The phrase “substantially without a step-up transmission ratio” is to beunderstood to mean, in particular, that at least one transmission ratiobetween the drive gearwheel and the output gearwheel is between 10 and1, advantageously between 5 and 1, particularly advantageously between 2and 1. The drive gearwheel and the output gearwheel preferably have anidentical rotational speed during operation. The drive gearwheel and theoutput gearwheel preferably have an identical rotational directionduring operation, that is to say they rotate in an identical directionin relation to the direction in terms of action. “Provided” is to beunderstood to mean, in particular, configured and/or equippedspecifically. The phrase “couple such that they can be moved relative toone another about a pivot axis” is to be understood to mean, inparticular, that the connecting unit makes pivoting of the rotationalaxis of the output gearwheel relative to the rotational axis of thedrive gearwheel possible, the connecting unit being provided fortransmitting the rotational movement from the drive gearwheel to theoutput gearwheel in various positions of the rotational axis of theoutput gearwheel relative to the rotational axis of the drive gearwheel.The connecting unit is preferably provided for coupling the drivegearwheel and the output gearwheel in at least two, advantageously atleast three different pivoting positions. The connecting unit isparticularly advantageously provided for coupling the drive gearwheeland the output gearwheel over a pivoting range of at least 60°,advantageously at least 120°, particularly advantageously at least 180°.As a result of the embodiment according to the disclosure of thehand-held tool gear mechanism unit, it is possible to work at locationswhich are close to the edge and can be reached only with particulardifficulty, because a rotational axis of the insertable tool is arrangedclose to a pivot housing face which runs parallel to said rotationalaxis and the rotational axis can be pivoted relative to a main extent ofthe hand-held tool. As a result of the embodiment according to thedisclosure of the hand-held tool gear mechanism unit, working close tothe edge is no longer restricted by a diameter of a drive unit, inparticular a gear mechanism of the drive unit, of the hand-held tool.

It is proposed in another embodiment that the pivot axis is orientedperpendicularly with respect to the rotational axis of the drivegearwheel, as a result of which a structurally simple pivoting mechanismcan be used. “Oriented perpendicularly” is to be understood to mean, inparticular, that the pivot axis is oriented parallel to a plane whichhas a 90° angle with respect to the rotational axis of the drivegearwheel. The pivot axis preferably intersects the rotational axis ofthe drive gearwheel at a right angle. The pivot axis advantageouslyintersects the rotational angle of the output gearwheel at a rightangle.

Furthermore, it is proposed that the connecting unit has at least onegearwheel which is configured as a bevel gearwheel, as a result of whichan efficient transmission of the torque can be achieved in astructurally simple manner. A “bevel gearwheel” is to be understood tomean a gearwheel which has a basic shape of a truncated cone and thecircumferential face of which is toothed.

Furthermore, it is proposed that the connecting unit has two gearwheelswhich are arranged separately from one another, as a result of which therotational axis of the drive gearwheel can be spaced apart from therotational axis of the output gearwheel in a structurally simple manner.The phrase “have two gearwheels which are arranged separately from oneanother” is to be understood to mean, in particular, that the connectingunit has a first gearwheel which meshes with the drive gearwheel and asecond gearwheel which is different from the first gearwheel and mesheswith the output gearwheel.

In addition, it is proposed that the gearwheels of the connecting unitare arranged between the rotational axis of the drive gearwheel and therotational axis of the output gearwheel, as a result of which aconstruction is possible which is particularly stable and subject to lowwear. In this context, “between” is to be understood to mean, inparticular, that the connecting unit lies on a straight line whichintersects the rotational axis of the drive gearwheel and the rotationalaxis of the output gearwheel, in particular, at a right angle. As analternative, merely that gearwheel of the connecting unit which mesheswith the output gearwheel could be arranged between the rotational axisof the drive gearwheel and the rotational axis of the output gearwheel.The gearwheel which meshes with the drive gearwheel is preferablyarranged on a side of the rotational axis of the drive gearwheel, whichside faces away from the rotational axis of the output gearwheel.

Furthermore, it is proposed that the hand-held tool gear mechanism unitcomprises a bearing apparatus which mounts a shaft of the connectingunit at two points, between which at least one of the gearwheels of theconnecting unit is arranged, as a result of which a construction can beachieved which is particularly stable and subject to low wear. A“bearing apparatus” is to be understood to mean, in particular, anapparatus which is provided for bringing about at least one bearingforce on the shaft of the connecting unit, which bearing force fastensthe shaft rotatably. A “shaft of the connecting unit” is to beunderstood to mean, in particular, a shaft which connects the gearwheelsof the connecting unit fixedly to one another so as to rotate together.The phrase “at two points” is to be understood to mean, in particular,that the bearing apparatus has two bearing means which act on the shaftof the connecting unit at different points.

It is proposed in one advantageous embodiment of the disclosure that thehand-held tool gear mechanism unit has a drive shaft which is configuredat least partially integrally with the drive gearwheel, as a result ofwhich low production costs are possible. A “drive shaft” is to beunderstood to mean, in particular, a shaft which transmits therotational movement from the direction of the drive unit of thehand-held tool to the drive gearwheel. “Configured at least partiallyintegrally” is to be understood to mean, in particular, that the driveshaft and the drive gearwheel are connected to one another in amaterial-to-material manner, such as by way of a welding process, anadhesive bonding process and/or advantageously by way of being machinedout of a single blank. The drive gearwheel is preferably cut onto thedrive shaft.

It is proposed in a further embodiment that the hand-held tool gearmechanism unit has an output shaft which is configured at leastpartially integrally with the output gearwheel, as a result of which lowproduction costs can be achieved. An “output shaft” is to be understoodto mean, in particular, a shaft which, during operation, transmits arotational movement away from the output gearwheel in the direction ofthe insertable tool fastening means.

Furthermore, it is proposed that the hand-held tool gear mechanism unithas a coupling apparatus which is provided for producing a connection toa hand-held tool, which connection can be disconnected by an operator,as a result of which the hand-held tool can be used in an optimum mannerin different working situations. A “coupling apparatus” is to beunderstood to mean, in particular, an apparatus which is provided forfastening a pivoting housing of the hand-held tool gear mechanism unitto the hand-held tool in a non-positive and/or positively lockingmanner. The coupling apparatus preferably locks the pivoting housing ofthe hand-held tool gear mechanism unit to the hand-held tool. The phrase“can be disconnected by an operator” is to be understood to mean, inparticular, that the connection is configured such that it can bereleased by the operator without destruction. The coupling apparatus isadvantageously provided for producing a connection to a hand-held tool,which connection can be disconnected without tools. A “hand-held tool”is to be understood to mean a hand-held tool which appears appropriateto a person skilled in the art, but advantageously a power drill, ahammer and/or percussion drill or particularly advantageously ascrewdriver.

Furthermore, it is proposed that the hand-held tool gear mechanism unitcomprises an articulation closure which is provided for closing apivoting region at least partially, as a result of which penetration ofdirt and moisture into the pivoting housing of the hand-held tool gearmechanism unit can be reduced advantageously. A “pivoting region” is tobe understood to mean, in particular, a region, through which at leastthe output shaft, the drive shaft, the insertable tool fastening meansand/or an insertable tool which is fastened in the insertable toolfastening means emerges from a pivoting housing of the hand-held toolgear mechanism unit in at least one of a plurality of possible positionsaround the pivot axis. The phrase “close at least partially” is to beunderstood to mean, in particular, that the articulation closure coversmore than 50%, advantageously more than 75%, particularly advantageouslymore than 90% of the part of the pivoting region which is uncovered bythe output shaft and/or the insertable tool fastening means, by theoutput shaft, the insertable tool fastening means and/or the insertabletool which is fastened in the insertable tool fastening means.

In addition, it is proposed that the articulation closure has at leasttwo sprung closure segments, as a result of which particularlysatisfactory protection against penetrating dirt and against penetratingmoisture can be achieved. A “closure segment” is to be understood tomean, in particular, a part of the articulation closure which isprovided for closing a part of the pivoting region at least partially.The term “sprung” is to be understood to mean, in particular, that theclosure segments are mounted such that they can be displaced counter toat least one spring element.

Furthermore, the disclosure proceeds from a hand-held tool having ahand-held tool gear mechanism unit according to the disclosure.

It is proposed that the hand-held tool has a drive unit, the rotationalaxis of the drive gearwheel and a rotational axis of the drive unitbeing at least substantially identical. A “drive unit” is to beunderstood to mean, in particular, a unit which is provided forproducing a rotational movement which is suitable for a workingoperation. The drive unit preferably comprises a motor and a gearmechanism which is provided for converting a rotational movement of apart of the motor into the rotational movement which is suitable for theworking operation. The phrase “at least substantially identical” is tobe understood to mean, in particular, that the rotational axis of thedrive gearwheel and the rotational axis of the drive unit are spacedapart by less than 15 mm, advantageously less than 10 mm, particularlyadvantageously less than 5 mm, in a volume of the hand-held tool and thehand-held tool gear mechanism unit. The rotational axis of the drivegearwheel and the rotational axis of the drive unit particularlypreferably lie on an identical straight line. An advantageous, inparticular space-saving construction is possible as a result of theembodiment according to the disclosure of the hand-held tool.

Furthermore, it is proposed that the machine housing has an overalllength of less than 180 mm, as a result of which a hand-held tool can beprovided which can be used in particularly constricted workinglocations. A “machine housing” is to be understood to mean, inparticular, a housing which encloses modules of the hand-held tool in aprotected manner and connects them to one another. The hand-held tool,in particular together with a hand-held tool gear mechanism unit whichis coupled to the hand-held tool, preferably has an overall length ofless than 180 mm parallel to a rotational axis of the insertable toolfastening means.

Here, the hand-held tool gear mechanism unit according to the disclosureand the hand-held tool according to the disclosure are not to berestricted to the above-described application and embodiment. Inparticular, the hand-held tool gear mechanism unit according to thedisclosure and the hand-held tool according to the disclosure can have anumber which differs from a number mentioned herein of individualelements, components and units for fulfilling a method of operationwhich is described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages result from the following description of the drawing.Three exemplary embodiments of the disclosure are shown in the drawing.The drawing, the description and the claims contain numerous features incombination. A person skilled in the art will expediently also considerthe features individually and combine them to form appropriate furthercombinations.

In the drawing:

FIG. 1 shows a hand-held tool having a hand-held tool gear mechanismunit according to the disclosure in a side view,

FIG. 2 shows the hand-held tool gear mechanism unit from FIG. 1 in asectional illustration,

FIG. 3 shows a sectional illustration of an alternative exemplaryembodiment of the hand-held tool gear mechanism unit from FIG. 1 havingan articulation closure which comprises sprung closures segments,

FIG. 4 shows the articulation closure of the hand-held tool gearmechanism unit from FIG. 3 in a perspective illustration,

FIG. 5 shows a sectional illustration of an alternative exemplaryembodiment of the hand-held tool gear mechanism unit from FIG. 1 havingan articulation closure which comprises a closure belt, and

FIG. 6 shows the articulation closure of the hand-held tool gearmechanism unit from FIG. 5 in a perspective illustration.

DETAILED DESCRIPTION

FIG. 1 shows a hand-held tool 38 a which is configured as a screwdriver.The hand-held tool 38 a comprises a hand-held tool gear mechanism unit10 a according to the disclosure, a drive unit 46 a, a pistol-shapedmachine housing 50 a, a rechargeable battery 54 a, electronics 56 a andan operating element 58 a. The hand-held tool gear mechanism unit 10 ais connected fixedly to the hand-held tool 38 a, but could also beconnected such that it can be disconnected by an operator. Thediagrammatically shown drive unit 46 a comprises, in a manner which isnot shown in greater detail here, an electric motor and a gear mechanismwhich reduces a rotational movement of the electric motor during aworking operation to a rotational speed which is suitable for screwingand provides counterclockwise rotation and clockwise rotation. Theelectronics 56 supply the electric motor with electric power from therechargeable battery 54 in a manner which is dependent on an operatorinput via the operating element 58.

The hand-held tool gear mechanism unit 10 a comprises a drive gearwheel12 a, an output gearwheel 14 a, a connecting unit 20 a, a bearingapparatus 28 a, a drive shaft 32 a, an output shaft 34 a, an insertabletool fastening means 60 a and a pivoting housing 62 a. The pivotinghousing 62 a is configured as at least one plastic part. Here, thepivoting housing 62 a consists of two housing shells which are connectedin a material-to-material manner.

The drive shaft 32 a is connected fixedly to a part of the drive unit 46a and the drive gearwheel 12 a so as to rotate with them. Duringoperation, the drive unit 46 a drives the gearwheel 12 a and the driveshaft 32 a rotationally about a rotational axis 16 a of the drivegearwheel 12 a. The rotational axis 16 a of the drive gearwheel 12 acannot be moved relative to the machine housing 50 a. In a manner whichis not shown in greater detail here, the drive shaft 32 a is mounted inthe machine housing 50 a such that it can be rotated about therotational axis 16 a. The drive gearwheel 12 a is configured as a bevelgearwheel. It is configured integrally with the drive shaft 32 a. As analternative, a drive gearwheel could be pressed and/or fastened in apositively locking manner onto a drive shaft.

The drive gearwheel 12 a meshes with a first gearwheel 24 a of theconnecting unit 20 a. The first gearwheel 24 a is configured as a bevelgearwheel. A shaft 30 a of the connecting unit 20 a connects the firstgearwheel 24 a to a second gearwheel 26 a of the connecting unit 20 a. Arotational axis 64 a of the connecting unit 20 a is orientedperpendicularly with respect to the rotational axis 16 a of the drivegearwheel 12 a. The second gearwheel 26 a of the connecting unit 20 a isconfigured as a bevel gearwheel. The two gearwheels 24 a, 26 a of theconnecting unit 20 a are arranged separately from one another. Thesecond gearwheel 26 a of the connecting unit 20 a meshes with the outputgearwheel 14 a.

A rotational axis 18 of the output gearwheel 14 a is orientedperpendicularly with respect to the rotational axis 64 a of theconnecting unit 20 a. The rotational axis 16 a of the drive gearwheel 12a is arranged such that it is spaced apart radially from the rotationalaxis 18 a of the output gearwheel 14 a by approximately 18 mm. Theconnecting unit 20 a is therefore provided for coupling the drivegearwheel 12 a and the output gearwheel 14 a such that they can be movedrelative to one another about a pivot axis 22 a. The gearwheels 24 a, 26a of the connecting unit 20 a are arranged between the rotational axis16 a of the drive gearwheel 12 a and the rotational axis 18 a of theoutput gearwheel 14 a.

The drive gearwheel 12 a and the output gearwheel 14 a have an identicalnumber of teeth. The two gearwheels 24 a, 26 a of the connecting unit 20a have an identical number of teeth. The connecting unit 20 a thereforetransmits a rotational movement from the drive gearwheel 12 a to theoutput gearwheel 14 a without a step-up transmission ratio.

The output shaft 34 a is configured integrally with the output gearwheel14 a. The output shaft 34 a is mounted in the pivoting housing 62 a ofthe hand-held tool gear mechanism unit 10 a by way of a bearing means 74a of the hand-held tool gear mechanism unit 10 a such that it can berotated about the rotational axis 18 a. The output shaft 34 a connectsthe output gearwheel 14 a fixedly to the insertable tool fastening means60 a of the hand-held tool gear mechanism unit 10 a so as to rotate withit. The insertable tool fastening means 60 a is provided as a bitholder. To this end, the insertable tool fastening means 60 a delimitsan insertable tool receiving space 76 a by way of a hexagonal base face.

The bearing apparatus 28 a mounts the pivoting housing 62 a of thehand-held tool gear mechanism unit 10 a such that it can be pivotedrelative to the machine housing 50 a. To this end, the bearing apparatus28 a has a first bearing means 66 a and a second bearing means 68 awhich mount the connecting unit 20 a rotatably in the machine housing 50a. The first gearwheel 24 a and the second gearwheel 26 a of theconnecting unit 20 a are arranged between the first bearing means 66 aand the second bearing means 68 a. The bearing apparatus 28 a thereforemounts the shaft 30 a of the connecting unit 20 a at two points, betweenwhich the two gearwheels 24 a, 26 a of the connecting unit 20 a arearranged.

The bearing apparatus 28 a has a third bearing means 70 a and a fourthbearing means 72 a which mount the pivoting housing 62 a of thehand-held tool gear mechanism unit 10 a on the shaft 30 a of theconnecting unit 20 a such that it can be pivoted relative to the machinehousing 50 a. The first gearwheel 24 a and the second gearwheel 26 a ofthe connecting unit 20 a are arranged between the third bearing means 70a and the fourth bearing means 72 a. As an alternative, a fourth bearingmeans which is arranged so as to lie closer to a drive gearwheel than athird bearing means could be arranged between two gearwheels of aconnecting unit. The pivot axis 22 a and the rotational axis 64 a of theconnecting unit 20 a therefore lie on an identical line. The pivot axis22 a of the pivoting housing 62 a is oriented perpendicularly withrespect to the rotational axis 16 a of the drive gearwheel 12 a. Themachine housing 50 a has a pivoting cutout 78 a which makes pivoting ofthe pivoting housing 62 a possible about a pivoting angle ofapproximately 180°.

The output gearwheel 14 a has a maximum diameter 84 a which is at mosttwice as large as a maximum diameter 86 a of the output shaft 34 a.Here, the output gearwheel 14 a and the output shaft 34 have anidentical diameter 84 a, 86 a, and, to be precise, the output gearwheel14 a has a maximum diameter 84 a of less than 15 mm, namely ofapproximately 8 mm. The insertable tool fastening means 60 a has amaximum diameter 87 a which is at most twice as large as a maximumdiameter 86 a of the output shaft 34 a, and, to be precise, theinsertable tool fastening means 60 a has a diameter 87 a of less than 16mm, namely of approximately 12 mm. The maximum diameter 84 a of theoutput gearwheel 14 a and the maximum diameter 87 a of the insertabletool fastening means 60 a differ by less than 50% of the maximumdiameter 84 a of the output gearwheel 14 a. The machine housing 50 a hasan overall length 52 a of less than 180 mm, namely of approximately 115mm. In addition, the machine housing 50 a has an overall height 82 aperpendicularly with respect to the total length 52 a of less than 200mm, namely of approximately 140 mm. A rotational axis 16 a of the drivegearwheel 12 a and a rotational axis 48 a of the drive unit 46 a areidentical, that is to say they lie on an identical line.

FIGS. 3 to 6 show two further exemplary embodiments of the disclosure.The following descriptions and the drawings are restricted substantiallyto the differences between the exemplary embodiments, it being possiblein principle for reference also to be made to the drawings and/or thedescription of the other exemplary embodiments, in particular FIGS. 1and 2, with regard to components with an identical designation, inparticular in relation to components with identical reference numerals.In order to distinguish between the exemplary embodiments, the letter ais placed after the reference numerals of the exemplary embodiment inFIGS. 1 and 2. The letter a is replaced by the letters b or c in theexemplary embodiments of FIGS. 3 to 6.

FIG. 3 shows a part of a hand-held tool 38 b having a hand-held toolgear mechanism unit 10 b. The hand-held tool gear mechanism unit 10 bcomprises at least one drive gearwheel 12 b, an output gearwheel 14 b, aconnecting unit 20 b and a pivoting housing 62 b. A rotational axis 16 bof the drive gearwheel 12 b is spaced apart radially from a rotationalaxis 18 b of the output gearwheel 14 b by approximately 18 mm. Duringoperation, the connecting unit 20 b transmits a rotational movement fromthe drive gearwheel 12 b to the output gearwheel 14 b without a step-uptransmission ratio. The connecting unit 20 b is provided for couplingthe drive gearwheel 12 b and the output gearwheel 14 b such that theycan be moved relative to one another about a pivot axis 22 b.

FIG. 4 shows an articulation closure 40 b of the hand-held tool gearmechanism unit 10 b. The articulation closure 40 b of the hand-held toolgear mechanism unit 10 b is provided for closing a pivoting region 42 bat least partially. The output shaft 34 b and the pivoting housing 62 bextend through the pivoting region 42 b. The pivoting region 42 b isarranged on a side of the pivoting housing 62 b, which side faces aninsertable tool fastening means 60 b of the hand-held tool gearmechanism unit 10 b. The articulation closure 40 b comprises a row ofsprung closure segments 44 b which are displaced during a movement ofthe pivoting housing 62 b, as a result of which the pivoting region 42 bis covered. To this end, the closure segments 44 b are pressed bysprings 88 b in the direction of the pivoting housing 62 b. The closuresegments 44 b are of rounded configuration on a side which faces awayfrom the springs 88 b. The closure segments 44 b are guided on two sideswhich lie in the movement direction, as a result of which the risk thatthe closure segments 44 b are pressed inward can be minimizedadvantageously.

FIG. 5 shows a system having a partially illustrated hand-held tool 38 cand a hand-held tool gear mechanism unit 10 c. The hand-held tool gearmechanism unit 10 c comprises at least one drive gearwheel 12 c, anoutput gearwheel 14 c, a connecting unit 20 c, an articulation closure40 c, an insertable tool fastening means 60 c and a pivoting housing 62c. A rotational axis 16 c of the drive gearwheel 12 c is spaced apartradially from a rotational axis 18 c of the output gearwheel 14 c byapproximately 18 mm. During operation, the connecting unit 20 ctransmits a rotational movement from the drive gearwheel 12 c to theoutput gearwheel 14 c without a step-up transmission ratio. Theconnecting unit 20 c is provided for coupling the drive gearwheel 12 cand the output gearwheel 14 c such that they can be moved relative toone another about a pivot axis 22 c.

The hand-held tool gear mechanism unit 10 c has a coupling apparatus 36c which is provided for producing a connection to a hand-held tool 38 c,which connection can be disconnected by an operator. The couplingapparatus 36 c comprises an operating element 90 c, a fastening means 92c and a fixing means 94 c. The operating element 90 c is of annularconfiguration and is mounted rotatably on the pivoting housing 62 c. Thefastening means 92 c is provided for producing a positively lockingconnection with an undercut of the hand-held tool 38 c during a rotationof the operating element 90 c. The fixing means 94 c is provided forcoupling the pivoting housing 62 c in an axially fixed manner to thehand-held tool 38 c so as to rotate with it in the case of anestablished positively locking connection. In addition, in a mannerwhich is not shown in greater detail here, the operating element 90 c issprung, as a result of which accidental release is avoided. The couplingapparatus 36 c is provided for coupling with the hand-held tool 38 c indifferent orientations relative to the hand-held tool 38 c, as a resultof which the pivot axis 22 c can be oriented differently with respect tothe hand-held tool 38 c.

The pivoting housing 62 c is configured in two parts. A first part 96 cof the pivoting housing 62 c is fixed relative to the hand-held tool 38c during a working operation. A second part 98 c (shown in FIG. 6) ofthe pivoting housing 62 c is mounted such that it can be pivotedrelative to the hand-held tool 38 c. The first part 96 c of the pivotinghousing 62 c has two guide grooves 104 c, 106 c which mount the part 98c of the pivoting housing 62 c pivotably. Here, the second part 98 c canbe pivoted by more than 180° relative to the first part 96 c.

The articulation closure 40 c is provided for closing two laterallyarranged pivoting regions 42 c. To this end, the articulation closure 40c comprises an annular belt 100 c which keeps the pivoting regions 42 cclosed, in particular completely, during pivoting of the pivotinghousing 62 c. The connecting unit 20 c is guided into the annular belt100 c from a side which faces the drive gearwheel 12 c. The outputgearwheel 14 c is arranged within the annular belt 100 c. A drive shaft32 c of the hand-held tool gear mechanism unit 10 c is connected fixedlyto a drive means 102 c so as to rotate with it, which drive means 102 cis driven directly by the hand-held tool 38 c during operation. Thedrive means 102 c is of hexagonal configuration. It can therefore bedriven by an insertable tool fastening means 108 c of the hand-held tool38 c.

What is claimed is:
 1. A hand-held tool gear mechanism unit, comprising:a drive gearwheel; an output gearwheel having a rotational axis spacedapart radially from a rotational axis of the drive gearwheel; and aconnecting unit configured to transmit a rotational movement from thedrive gearwheel to the output gearwheel substantially without a step-uptransmission ratio, wherein the connecting unit couples the drivegearwheel and the output gearwheel in such a way that the drivegearwheel and the output gearwheel are pivotable relative to one anotherabout a pivot axis.
 2. The hand-held tool gear mechanism unit accordingto claim 1, further comprising: a pivoting housing in which the outputgearwheel is mounted, the pivoting housing being mounted pivotably onthe connecting unit.
 3. The hand-held tool gear mechanism unit accordingto claim 1, wherein the pivot axis is oriented perpendicularly withrespect to the rotational axis of the drive gearwheel.
 4. The hand-heldtool gear mechanism unit according to claim 1, wherein the connectingunit has at least one gearwheel configured as a bevel gearwheel.
 5. Thehand-held tool gear mechanism unit according to claim 1, wherein theconnecting unit has two gearwheels arranged separately from one another.6. The hand-held tool gear mechanism unit according to claim 5, whereinthe gearwheels of the connecting unit are arranged between therotational axis of the drive gearwheel and the rotational axis of theoutput gearwheel.
 7. The hand-held tool gear mechanism unit according toclaim 5, further comprising: a bearing apparatus mounting a shaft of theconnecting unit at two points, wherein at least one of the gearwheels ofthe connecting unit is arranged between the two points.
 8. The hand-heldtool gear mechanism unit according to claim 7, further comprising: apivoting housing in which the output gearwheel is mounted, the pivotinghousing being mounted pivotably on the shaft of the connecting unit bythe bearing apparatus.
 9. The hand-held tool gear mechanism unitaccording to claim 1, further comprising a drive shaft configured atleast partially integrally with the drive gearwheel.
 10. The hand-heldtool gear mechanism unit according to claim 1, further comprising anoutput shaft configured at least partially integrally with the outputgearwheel.
 11. The hand-held tool gear mechanism unit according to claim1, further comprising: a coupling apparatus configured to produce aconnection to a hand-held tool, wherein the coupling apparatus isfurther configured so that the connection is terminable in response toan operator action.
 12. A hand-held tool, comprising: a hand-held toolgear mechanism unit, including: a drive gearwheel; an output gearwheelhaving a rotational axis spaced apart radially from a rotational axis ofthe drive gearwheel; and a connecting unit configured to transmit arotational movement from the drive gearwheel to the output gearwheelsubstantially without a step-up transmission ratio, wherein theconnecting unit couples the drive gearwheel and the output gearwheel insuch a way the drive gearwheel and the output gearwheel are pivotablerelative to one another about a pivot axis.
 13. The hand-held toolaccording to claim 13, further comprising a machine housing having anoverall length of less than 180 mm.
 14. A system comprising: a hand-heldtool, including: a hand-held tool gear mechanism unit, including: adrive gearwheel; an output gearwheel having a rotational axis spacedapart radially from a rotational axis of the drive gearwheel; aconnecting unit configured to transmit a rotational movement from thedrive gearwheel to the output gearwheel substantially without a step-uptransmission ratio; and a coupling apparatus configured to produce aconnection to the hand-held tool, wherein the connecting unit couplesthe drive gearwheel and the output gearwheel in such a way the drivegearwheel and the output gearwheel are pivotable relative to one anotherabout a pivot axis, and wherein the coupling apparatus is furtherconfigured so that the connection is terminable in response to anoperator action.